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…The k-sample Anderson-Darling test is a nonparametric statistical procedure that tests the
hypothesis that the populations from which two or more groups of data were drawn are identical.
The distinct values in the combined data set are ordered from smallest to largest, denoted z(1),
z(2),… z(L), where L will be less than n if there are tied…
https://www.wichita.edu/industry_and_defense/NIAR/Research/cytec-ep2202/IM7G-Unitape-3.pdf